This invention relates to an energy absorbing beam and more particularly to a beam in a vehicle door structure intended to absorb impact energy when a vehicle occupant impacts the interior of the door during a collision.
During a vehicle collision, the occupants in the vehicle will often impact interior components of the vehicle and thereby receive injuries. During a side impact collision, the occupants are often thrust sideways into the door. In an effort to reduce injuries from impacting the door, the Federal Government has proposed regulations requiring energy absorbing features to reduce the impact force experienced by the occupants and thus eliminate injury or reduce its severity.
The present invention is intended to increase the energy absorption of a vehicle door by providing a hollow beam extending longitudinally through the door structure that is configured to collapse upon impact in a predetermined manner to absorb energy. The beam collapses before substantial transverse deflection of the beam caused by the impact. In cross-section, the beam is a parallelogram that bends at the four corners upon impact to collapse the beam, thus absorbing energy. The particular dimensions of the beam can be varied depending on the particular application of the beam and the door length.
The beam can be incorporated into a conventional door assembly having an inner panel and door skin with a window regulator, latch mechanism, etc. mounted to the panel. In addition, the beam can be incorporated into a functional door cartridge which carries the window regulator, latch, etc. and is positioned between the inner panel and skin. The beam can include stiffening ribs to strengthen the beam as necessary, while additional energy absorbing materials can be placed within the beam or on the beam exterior facing the vehicle occupants. These and other modifications are all within the purview of the invention.
Further objects, features and advantages of the invention will become apparent from a consideration of the following description and the appended claims when taken in connection with the accompanying drawings.